A radar device is applied to various technical fields, and recently is installed in a vehicle to improve a mobility of the vehicle. Such a radar device uses electromagnetic waves to detect information about the surrounding environment of a vehicle. In addition, by using the corresponding information for moving a vehicle, efficiency of the movement of the vehicle can be improved. To this end, the radar device includes an antenna to transmit and receive electromagnetic waves.
Meanwhile, a vehicle radar may be classified into a long range radar (LRR) and a short range radar (SRR), and in the case of LRR, a frequency of 77 GHz band is mainly used, and in the case of SRR, a 24 GHz band is mainly used.
In order for a vehicle radar including both a LRR and a SRR to secure a field of view (FOV) and detection distance for simultaneously detecting objects placed at a long distance and a short distance, it is necessary to dispose an optimal interval between antenna channels and secure an antenna gain.